Motor-compressor



April 21, 1959 l R. HINTZE 2,883,099

MOTOR-COMPRESSOR Filed Jan. 12, 1956 INVENTGR. /f #ihfz 6 BY I I 1 w/Jm United States Patent MOTOR-COMPRESSOR Rudolf Hintze, Neuenhain uber Bad Soden (Taunus), Germany, assignor to Stempel-Hermetik G.m.b.H., Frankfurt am Main, Germany Application January 12, 1956, Serial No. 558,794 Claims priority, application Germany January 15, 1955 12 Claims. Cl. 230-58 The present invention relates to motor-compressors.

More particularly, the present invention relates to motor-compressors of the type which are hermetically sealed and used in household refrigerators, for example.

With such motor-compressors it is known to provide a carrier which is common to the motor as well as the compressor in order to provide a very compact arrangement. However, the motor-compressors known upto the present time areexpensive to manufacture particularly because of the difficulties in providing the suction and discharge valves for the cylinder of the compressor. It is conventional to locate these valves in the end wall of the cylinder, and this latter arrangement is exceedingly complicated and expensive because of the necessity for providing in the end wall of the cylinder a chamber for accommodating both the suction and thedischarge valves as wellas all of the structure associated with the suction and discharge valves.

One of the objectsof the present invention is to overcome the above drawbacks by providing an arrangement which is far less expensive than the conventionalgarrangement described above.

Another object of the present invention is to provide an arrangement where only one valve need be accommodated at the end wall of the cylinder of the compressor.

A further objectof the present invention is to provide a motor-compressor partwhich serves to mount the cylinder on the carrier of the motor-compressor with a structure which enables this part to additionally serve the function of housing a valve of the motor-compressor.

An additional object of the; present invention is to A 1 2,883,099 i d. P? 9.

2 of the cylinder for controlling the flow of fluid therefrom.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following descriptionv of specific embodiments when read in connection with the accentpanying drawings, in which:

Fig. 1 is a fragmentary, sectional, perspective, partly exploded view of a construction according to the present invention;

Fig. 2 is a plan view of the cylinder of the compressor with the block which mounts the cylinder on the carrier which is common to the compressor and themotor;

Fig. 2a is a fragmentary elevational view illustrating the manner in which the cylinder is fixed to the carrier;

Fig. 3 is a perspective exploded view .illustrating the structure of the suction valve of the cylinder;

Fig. 3a is a fragmentary sectional view further illustrating the structure of the suction valve of the cylinder;

Fig. 4 is a sectional elevational view onan enlarged scale illustrating the discharge valve structure according to the present invention; and r Fig. 5 is a fragmentary plan view taken along line 5- -5 of Fig. 4 in the direction of the arrows.'

Referring now to the drawings and to Fig. 1 in particular, it will be seen that a carrier 18 is provided for carrying both the motor and the compressor. This carrier 18 ismade of sheet metal and is suitably shaped as indicated in Fig. l for carrying both the motor and the compressor. The stator" of the motor isdirectly carried by the carrier 18, and at the upper left portion of Fig. 1 is shownthebearing of the motor which turn ably guides the motor shaft, this bearing being directly carried by the carrier 18, as indicated in Fig. 1. The motor shaft extends downwardly beyond the bearing shown at the upper left portion of Fig. l in a substantially vertical direction and is connected through a suit;- able crank to a piston which reciprocates in the cylinder 1 shown in Fig. 1, this cylinder, 1 forming part'of the compressor which is also carried by the carrier 18. The cylinder 1 is fixed to the carrier 18 through the medium of a block 2 which will be further described below.

The cylinder 1 has. an elongated end portion 3 of a. lesser thickness than the remainder of the cylinder "and joined to the remainder of the cylinder by a shoulder 4. An end wall 5 together with a sealing disc 6 formi'an end wall means for the cylinder, and this end. walll5 jis surrounded by the end portion 3 of. the cylinder andis with an end portion of a lesser wall thickness than the remainder of the cylinder and joined to the remainder of the cylinder by a shoulder in the interior of the cylinder. This end portion of the cylinder accommodates an end wall which is fixed to the cylinder and formed with a bore for admitting fluid into the interior of the cylinder. Between this end wall and the shoulder of the cylinder there is clamped a sealing disc which is formed with an elongated cutout in which is located a valve member for opening and closing the bore of the end wall of the cylinder. The cylinder is further formed with a lateral bore which communicates with a bore in a block which forms part of a mounting means for mounting the cylinder on the carrier. This mounting means'includes a discharge valve structure which communicates through a bore of the block with the interior spaced from the shoulder 4, in the manner indicated in Fig. 1.. The sealing disc 6 is clamped between the shbtil der 4 and the end wall 5, andthis clamping isbrought about by the free end portion of the cylinder which extends beyond the end wall 5 and which is rolled over in the manner indicated in Fig. 1 against the end wall 5 to fix the latter to the cylinder as well as to press the sealing disc 6 against end wall 5 and the shoulder This sealing disc 6 may be made .of any relatively soft metal such as lead or tin, or it may be made of a suit,- able plastic. The end wall 5 is formed with a substantiallyaxial bore 7 through which fluid to be compressed entersinto the cylinder 1 during the suction strokes of thepiston which lies therein. 7 At its face which is directedtoward the interior of the cylinder 1, the end wall 5 is. formed with an annular recess surrounding the bore 7 and pro viding at the inner face of the end wall 5 a valve seat portions. p 1", The sealingdisc 6 is formed, as is'shown mostblea'rlj 3, in Fig; 3, with an elongated diametr-al cutout 10 which is of a substantially rectangular configuration and which has narrow end portions 11, so as to provide the cutout 10. with lateral portions 12 which. are wider than the portions 11. The end portions 11 of the cutout 14 extend almost upto the periphery of the disc 6 and overrap the. shoulder 4, in the manner shown most clearly in Fig. 3a.

The valve. member 9 is in the form of an elongated metal strip, for example, and has a lesser thickness than the sealing disc 6, as shown in .Fig. 3a. This valve mernber..9foverlaps-with its free end portions the shoulder 4, so that, as indicated in Fig. 3a, the valve member 9 is freely movable between the shoulder 4 and the end wall 5.1within the limits provided by the difierence between the thickness of the sealing disc 6 and the valve member 9. As is indicated in Fig. 1,. the annular channel of the end, wall' whichforms the valve seat 8 is wider than the ,valve member 9, so that the latter is capable of engaging. the valve seat 8 without interference in order to close the bore 7.

The. operation. of the above described suction valve structure for the cylinder 1 is believed to be evident. Whenever. the piston in the cylinder 1 performs a suction stroke it will/automatically draw the valve member 9.. away from. the plate 5 to open the bore 7, while during the pressure. strokesof the piston the valve member 9 will be urged automatically into engagement with the valve seat 8 in order to close the bore 7.

The block 2 which serves to connect the cylinder 1 of the compressor to the carrier 18 is formed with a bore 13,'and a lateral wall portion of cylinder .1 is formed with abore which forms an extensionof the bore 13 and which. is tangential to the shoulder 4 and the disc 6, asisindicated in Fig. l.v These latter bores form the discharge bore. through..which-fluid under pressure is discharged .fromtheinteriorof thecylinder v1 during the compression strokes of the pistontherein.

Aschannel means22a .is fixed tothe carrier 18 in the manner indicated in Fig. llto form therewith a pressure chamber .22 which also serves as a noise reducing chamber.. This. pressure chamber 22 communicates with a discharge conduit 25. The channel means 22a includes apart opposite a .wall portion .of the carrier.18 and formed .with oneof a pair of openings 21 communicating with. the interior of the pressure chamber 22 t A wall. member 23a is fixed to the channel means 22a at its exterior wall and is also formed with an opening 21communicating with the opening 21 of the channel means 22a. Four side walls 23 are fixed to and extend fronrthe wall 23a to form therewith a substantially boxshaped structure which serves as a discharge valve chamber... A sealing ring 2a engages the free edges of the walls 23, and the block 2 engages the sealing ring 2a. Asis. indicated in Figs. 2 and 2a the block 2 is formed with'a pair of openings 19 through which a bolt extends into threaded engagement with a pair of the walls 23 in order to fix the block 2 to the walls 23, and in this way fix the cylinder 1 to the carrier 18, the cylinder 1 being directly fixed to the block 2. The. channel means 22a may be soldered or welded to the carrier 18, and the wall 23a may be soldered or welded to the channel means 22a, while the four walls 23 also may be soldered or welded to the wall 23a. Thus, it will be seen that the block 2 together with the walls 23aand 23 form a valve chamber 20 in which a discharge valve means is accommodated.

-'The. face 14 of the block 2 whichisxdirected toward the. interiorv of the enclosure 20 and away from the cylinder .1 is polished and isformed with an annular recess surrounding the bore 13 and providing at the interior of the enclosure 20 a valve seat 15. An elongated. valve member 16 having awidthwhioh is less than theouter diameter of the annular recess defining the valve seat 15 is 'adapted to engage the 'valve seat 15 for closing the assaoss.

- a 4L- bore 13 and to move away from the valve seat 15 for opening the bore. The structure of the discharge valve means is'shown most clearly in Figs. 4 and 5.

Thus, referring to Figs. 4 and 5 it will be seen that the block 2 has a pair of pins 17a fixed to and extending therefrom into the interior of the enclosure 20. These pins extend through a valve stop member 16a and into a pair of coil springs 17 in order to guide the latter. Thus, the springs 17 urge the valve stop member 16a toward the block 2, this valve stop member 16a being formed with bores through which the pins 17a freely extend. As is indicated in Fig. 4 the central portion of the valve stop member 16a is curved away from the block 2 and has a concave face directed toward the same.

The valve member 16 is located between the stop member 16a and the block 2, and this valve member 16 is formed at its ends portions with a pair of notches through which the pins 17a freely extend, as clearly indicated in Fig. 5. Thus, the springs 17 act through the member 16a to urge the valve 16 to its closed position, where the valve 16 engages the valve seat 15. However, when fluid under pressure is urged through the bore 13 from the cylinder 1 during the pressure strokes of the piston therein, the fluid under pressure is capable of moving thevalve member 16 away from the valve seat 15 into engagement with the central curved portion of the valve stop member 16a, and at thistime the fiuid under pressure can flow freely into the enclosure 20 and through the openings 21 into the pressure chamber 22 and from the latter through the discharge conduit 25. Duringv the suction strokes of the piston in the cylinder 1; the valve member 16 automatically .moves back to itsposition'engaging the valve seat 15 for closing the bore 13. Thus, the structure whichserves to mount. the cylinder '1 on the carrier 18 also serves to accommodate the discharge valve structure which cooperates with t'he compressor.

A suction chamber 24 which also serves as anoise reducing chamber is provided,- in the manner shown in Fig. 1, with a wall portion having a tubular extension 7a drawn therefrom, and this tubular extension 7a extends with a press fit into'the bore 7 of the end wall 5, so that in this exceedingly simple manner the suction chamber 24 is fixed directly to the end wall 5.

Thus, it will be seen that with the above described structure of the invention the end wall assembly ofthe cylinder is exceedingly simple, and the structure for mounting the cylinder on the carrier 18 also serves to accommodate the discharge valve structure for the cylinder. Thus, the cost of the assembly is greatly reduced. The unillustrated parts of the motor compressor are conventional and well known to those skilled inthe art;-

It will be understood thateach of the elements de' scribed above, or two or more together, may also find a useful application in other types of motor-compressors difiering from the types described above.

While the invention hasbeen illustrated and described as embodied in motor-compressors for household refrigerators and the'like, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from' the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of thisinvention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a motor-compressor, iii-combination, a cylinder forming of the cornpressor'and having an open'end,

portion of lesserwall thickness than the remainder of said cylinder joined to the remainder of said cylinder by a shoulder in the interior of said cylinder; an end wall surrounded by said open end portion of lesser thickness of said cylinder and closing said open end portion of said cylinder, said end wall being spaced from said shoulder; a sealing disc located between and engaging said end wall and said shoulder, said sealing disc being formed with a cutout and said end wall being formed with a bore communicating with said cutout; means for clamping said sealing disc between said shoulder and said end wall and for fixing said end wall to said cylinder; and a valve member of lesser thickness than said sealing disc located in said cutout thereof and adapted to move toward and away irom said end wall for closing and opening said bore thereof. I

2. In a motor-compressor, in combination, carrier means for carrying a motor and a compressor; a cylinder forming part of the compressor and having an end portion of a lesser thickness than the remainder of the cylinder and joined to the remainder of the cylinder by a shoulder located in the interior of said cylinder; mounting means fixed to a side of said cylinder adjacent said end portion thereof and mounting said cylinder on said canrier means, said mounting means including a block fixed directly to said cylinder and having a free face distant from said cylinder, said free face having a valve seat portion and said 'block being formed with a borewhich communicates with the interior of said cylinder and which is surrounded by said valve seat portion; first valve means located in said mounting means and cooperating with said valve seat portion of said block for controlling the flow of fluid in said cylinder; end wall means fixed to said cylinder and said end portion of lesser thickness and engaging said shoulder of said cylinder, said end wall means including an outer end Wall spaced from said shoulder and an inner sealing disc located between said shoulder and end wall, clamped between said shoulder and end wall, and formed with an elongated cutout extending substantially diametrically across said disc and overlapping said shoulder, said end wall being formed with -'a bore communicating with said cutout and surrounded at the face of said end wall directed toward the interior of said cylinder with a second valve seat portion; and an elongated valve member of a lesser thickness than said disc located in said elongated cutout thereof, having 'a pair of free end portions overlapping said shoulder of said cylinder, and adapted to move into and out of engagement with said second valve seat portion for closing and opening said bore in said end wall.

3. In a motor-compressor, in combination, carrier means for carrying a motor and a compressor; a cylinder forming part of the compressor and having an end portion of a lesser thickness than the remainder of the cylinder and joined to the remainder of the cylinder by a shoulder located in the interior of said cylinder; mounting means fixed to a side of said cylinder adjacent said end portion thereof and mounting said cylinder on said carrier means, said mounting means including a block fixed directly to said cylinder and having a free face distant from said cylinder, said free face having a valve seat portion and said block being formed with a bore which communicates with the interior of said cylinder and which is surrounded by said valve seat portion; first valve means located in said mounting means and cooperating with said valve seat portion of said block for controlling the flow of fluid in said cylinder; end wall means fixed to said cylinder and said end portion of lesser thickness and engaging said shoulder of said cylinder, said end wall means including an outer end wall spaced from said shoulder and an inner sealing disc located between said shoulder and end wall, clamped between said shoulder and end wall, and formed with an elongated cutout extending substantially diametrically across said disc and overlapping said shoulder, said end wall being formed with a bore conmrunicating with said cutout and surrounded at the face of said end wall directed toward the interior of said cylinder with a second valve seat portion; and an elongated valve member of a lesser thickness than said disc located in said elongated cutout thereof, having a pair of free end portions overlapping said shoulder of said cylinder, and adapted to move into and out of engagement with said second valve seat portion for closing and opening said bore in said end wall, said cylinder being formed with a bore extending substantially radially from the axis of said cylinder, and being tangential to said sealing disc, and forming an extension of said bore of said block. 7

4. In a motor-compressor, in combination, carrier means for carrying a motor and a compressor; a cylinder forming part of the compressor and having an end portion of alesser thickness than the remainder of the cylinder and joined to the remainder of the cylinder by a shoulder located in the interior of said cylinder; mounting means fixed to a side of said cylinderadjacent said end portion thereof and mounting said cylinder on said carrier means, said mounting means including a block fixed directly to said cylinder and having a free face distant from said cylinder, said free face having a valve seat portion and said block being formed with a bore which communicates with the interior of said cylinder and which is surrounded by said valve seat portion; first Valve means located in said mounting means and cooperating with said valve seat portion of said block for controlling the flow of fluid in said cylinder; end wall means fixed to said cylinder and said end portion of lesser thickness and engaging said shoulder of said cylinder, said end wall means including an outer end wall spaced from said shoulder and an inner sealing disc located between said shoulder and end wall, clamped between said shoulder and end wall, and formed with an elongated cutout extending substantially diametrically across said disc and overlapping said shou:lder, said end wall being formed with a bore communicating with said cutout and surrounded at the face of said end wall directed toward the interior of said cylinder with a second valve seat portion; an elongated valve member of a lesser thickness than said disc located in said elongated cutout thereof, having a pair of free end portions overlapping said shoulder of said cylinder, and adapted to move into and out of engagement with said second valve seat portion for closing and opening said bore in said end wall; and a suction chamber having a wall portion provided with a tubular extension which extends with a press fit into said bore of said end wall.

5. In a motor-compressor, in combination, a cylinder forming part of the compressor and having an open end portion of a lesser Wall thickness than the remainder of said cylinder joined to the remainder of said cylinder by a shoulder in the interior of said cylinder; an end wall surrounded by said open end portion of lesser thickness of said cylinder and closing said open end portion of said cylinder, said end wall being spaced from said shoulder; a sealing disc located between and engaging said end wall and said shoulder, said end portion of said cylinder having a free peripheral portion extending beyond said end wall and rolled over against the same for clamping said sealing disc between said shoulder and end wall for fixing said sealing disc and end wall to said cylinder, said sealing disc being formed with an elongated cutout overlapping said shoulder and said end wall being formed with a bore communicating with said cutout; and an elongated valve member of a lesser thickness than said sealing disc located in said cutout thereof, having free end portions overlapping said shoulder, and adapted to move toward and away from said end wall for closing and opening said bore thereof.

6. In a motor-compressor, in combination, a cylinder having an end portion of a lesser thickness than the remainder of said cylinder joined to the remainder of 7, said cylinderby" a shoul'dei" in" theinteri'oi-" of said cylin der'; a sealing disc surrounded by said-end portion-of saidcylinder and locatedin said shoulder thereof, said sealing disc being formed with an elongated diametral cutout having opposed end portions which are narrower than the remainder of said cutout respectively overlapping said shoulder of said cylinder; an end wall fixed to saidend portion of said cylinder and forming an end wall of said cylinder, said end wall engaging said sealing disc and pressing the same against said shoulder and being formed with a bore communicating with said cutout of said sealing disc; and an elongated valve member longer than the diameter of the interior ofsaid cylinder at a portion thereof beyond said end portion of lesser thickness located in'said cutout and overlapping said shoulder of said cylinder, said-valve member having'in said narrower end portion 'of said sealing disc free ends, respectively, which are of a lesser width than said narrow end portionof said sealing disc-and said valve member having a lesser thickness than said-sealing discso as to be freely movable toward and away from said bore of said end wall.-

7. In-a'motor-compressor, in combination, a cylinder having an end portion of a lesser thickness than the remain'der'of said cylinder joined to the remainder of said cylinder by ashoulder in the interior of said cylinder; a sealing disc surrounded by said end-portion of said cylinder and located at said shoulder thereof, said sealing disc being formed with an elongated diametral cutout having opposed end portions which are narrower than the remainder of said cutout respectively overlapping said shoulder of said cylinder; an end wall fixed to said end portion of saidcylin'der and forming an end wall of said-cylinder, saiden'cl wall engaging said sealing disc and .pressing the same against said shoulder and being formed'with a borec'ommunicating with said cutout of said sealing disc; and anelongated valve member longer than the diameter of the interior of said cylinder at a portion thereof beyond said end portion of lesser thickness located in said cutout and overlapping said shoulder of said cylinder, said valve member having in said narrower end portions of said sealing disc cutout freeends', respectively, which are of a lesser width than said narrow end portions of said sealing disc cutout and said valve member having'a lesser thickness than said sealing disc soas to be freely movable toward and away from said bore of said end wall, said cylinder being formed with a substantially radial bore which-is tangential. to said sealing disc and shoulder, whereby said radial bore may serve as an outlet for compressed fluid while said bore of said end wall may serve as a suction inlet for admitting 'fiuid into the cylinder. I

- 8. In a motor-compressor, in combination, a carrier for carrying a motor and a compressor; a mounting member fixed to said carrier and having four side wall port-ions extending from said carrier and defining a chamher; a block fixed to said mounting member at said four wall portions thereof and closing said chamber, said block being formed with a bore communicating wtih the interior of said chamber; valve means in said chamber for closing and opening said bore; and a cylinder fixed at a lateral portion thereof to said block at the exterior of said chamher and formed in a'wall portion'thereof with a bore communicating with the inter-ior'of said cylinder and forming' an extension of the bore of-said block.

9; In a motor-compressor, in combination, a carrier for carrying a motor and a compressor; wall means fixed to's'aid carrier and forming a pressure chamber with a part of said carrier, said wall means having a wall portionlocated opposite said part of said carrier; a substantially box-shaped member fixed to said wall portion of said wall means at the exterior of said pressure chamber, said box-shapedmember having four side wall portions a'n'd an-end walhsaid end wall being fixed to said w-allportion of said wall-means and saidwall portion of said" wan.means and saidn end" wall being' 'forme'd with: openings which communicate with each other so that the interior of said box-shaped member communicateswitli the interior of said pressure chamber, said four side wall portions having free' edges distant from said pressure chamber; a block'fixed' to said freeedges of said box shapedmember and closing the same, said block'being formed with a bore passing therethrou'gh andhavi'ng-at its face in the interior of said box-shaped member a valve seat portion surrounding said bore; valve means located in said box-shaped member and cooperating with'said valve seat for admitting fluid into said box-shaped member and from the latter into said pressure chamber when fluid above agiven pressure flowsalong said bore of said block into said box-shaped member; and a-cylinder fixed at a lateral portion thereof to said block at the exterior of said box-shaped member and formed'with-a bore which communicateswith the interior of said cylinder and-forms an extension of the bore of said block, whereby when com pressed fluid in said cylinder is discharged through said bore of said cylinder into said bore of said block, the compressed fluid will flow into said pressure chamber through said box-shaped member.

10. ln'amotor-compressor, in combination,- a cylind'er forming part of the compressor-and having an open-end portion of lesser-wall thickness than the remainder-of said cylinder joined to the remainder'of said cylinder by" a shoulder in'the interior of said" cylinder; an end wall surrounded by said open end portion of lesse'r thickness of said cylinder and closing said open end portion'of said cylinder, said end wallbeing spaced from said shoulder; a'sealing disc located between and engaging said end'wall and said shoulder, said' sealing disc being formed with an elongated cutout overlapping said shoulderand-said end wall being formed witlra bore communicating with said cutout; meansfor clampingfsaid'sealing'disc between said shoulder and said end wall and for fixing said end wall to said cylinder; and an elongated valve member of lesser thickness than said sealing d-isc'locate'd in said out out thereof, having free end portionsoverlapping said shoulder; and adapted to move toward and away from said end wall for closing and opening said bore thereof.

11. In a motor-compressor, in combination, a cylinder forming part ofthe compressor and having'in the region of an openend thereof an annular face substantially nor mal to the axis of saidcylinder; a sealing disc abutting with one face thereof against said annular face of said cylinder and beingformed with an elongatedcutout'ove'r lapping said annular'face; an end wall abutting against the other face of said sealing disc and being formed with a bore communicating with said cutout; means for fastening said end wall to' said cylinder and forclamping said sealing disc between said-annular face and said end wall: and an elongated valve member of 'alesser thickness than said sealing disc located in said cutout'thereof, havingfree end portions overlapping said annular faceand adapted to move toward and away from said end wall for closing and opening said bore thereof.

12. In a motor-compressor, in combination, a carrier for carrying the motor and compressor, said carrier having a wall portion; channelmeans fixedto said wall portion of said carrier and forming a pressure chamber there with, said channel means having a part distant from said carrier wall portion formed with a bore'communicating with the interior of said pressure chamber; a wall fixedt-o said channel means at the exterior of said pressure sham ber and at saidpart of said channel meansforrned with said opening, said wall being formedwith an opening communicating with said opening of said part of said channel means; four side walls fixed to and extending from said wall fixed to said channel means to define an enclosure therewith; a block fixed to said side walls and defining with the latter and with said wall a closed enclosure communicating with said pressure chamber through said opening; said block being-formed with a-bore passing therethrough; valve means in said enclosure for closing and opening said bore; a cylinder fixed at an exterior side portion thereof to said block and formed with a lateral bore forming an extension of said block bore, said cylinder having an elongated end portion of a lesser thickness than the remainder of said cylinder and joined to the remainder of said cylinder by a shoulder located in the interior of said cylinder; a sealing disc located in said cylinder against said shoulder thereof and formed with an elongated diametral cutout overlapping said shoulder; an end wall fixed to said end portion of said cylinder and pressing said sealing disc against said shoulder, said end wall being formed with a bore communicating with the interior of said cylinder through said cutout of said sealing disc, said end portion of said cylinder having a free 15 ,94 ,33

peripheral portion extending beyond said. end wall and .being rolled over against the same to clamp said sealing disc between said end wall and shoulder; and an elongated valve member in said cutout of said sealing disc, of a lesser thickness than said sealing disc, having free end portions respectively overlapping said shoulder, and being freely movable toward and away from said bore of said end wall for closing and opening the same.

References Cited in the file of this patent UNITED STATES PATENTS Durup Mar. 6, 1917 Rocciola July 14, 1931 Terry Jan. 30, 1934 

